Transfer of Delayed Hypersensitivity to Coccidioidin in Man

Abstract

Summary and Conclusions Generalized delayed sensitivity to coccidioidin can be transferred in human subjects with DNase-treated leukocyte extracts obtained from sensitive donors. This has been accomplished in 23 out of 27 consecutive attempts with leukocyte extracts obtained from moderately to markedly sensitive donors, and in 5 out of 8 consecutive attempts with leukocytes obtained from minimally to moderately sensitive donors. Attempts to transfer coccidioidin sensitivity with leukocyte extracts obtained from a negative donor were unsuccessful in 8 out of 9 consecutive trials. Sensitivity to coccidioidin after transfer may persist up to 15 months, in the absence of exposure to Coccidioides immitis or repeated skin testing. The results of transfer of coccidioidin sensitivity by this means generally parallel those obtained in man following the transfer of bacterial hypersensitivity using extracts of specifically sensitive donor leukocytes.